Climate Change is a Threat to Health: Greater Threat from Vector-borne Disease

Rising temperatures and increased rainfall from climate change can increase the spread of many infectious diseases, as these conditions benefit disease-carrying insects and animals.

Mosquitoes, for example, transmit diseases like West Nile Virus and Dengue fever. Mosquitoes find breeding grounds in the standing water that results from the more frequent downpours and flooding associated with climate change. Mosquitoes also reproduce more rapidly, bite more often and transmit diseases more efficiently at higher temperatures.

Regional warming may allow disease-carrying insects and animals to thrive in new areas. In the U.S., this could put previously unexposed populations at risk of Lyme disease, dengue fever, and Rocky Mountain spotted fever. Patterns of longer warm seasons may also allow disease-carrying insects to thrive for longer periods of time.

Diseases such as anthrax, blackleg, and hemorrhagic septicemia, all of which are sensitive to temperature and precipitation, may also follow this pattern of extended range and longer infection seasons.

People in developing countries, and the poor in developed countries, already experience a disproportionate share of the global infectious disease burden and are especially at risk. Preventing the spread of insect-borne disease depends both on mitigating climate change and on adequate disease prevention, such as proper insect control and access to health care.

For more information on the impacts of climate change on insect-borne disease, download PSR's fact sheet: Insect-Borne Diseases (PDF)